By Whitney Stidom, vice president of consumer enablement, eHealth

If you are among the 57 million Americans enrolled in a Medicare Advantage or Part D prescription drug plan, you should see an important piece of mail in your mailbox soon — assuming you don’t overlook it.

Before the end of September, anyone enrolled in Medicare Advantage or a Part D prescription drug plan should receive their Annual Notice of Change (ANOC) letter, which summarizes how the plan’s benefits, cost-sharing requirements and provider networks will change for next year.

Mail like this can easily be discarded as junk, which can leave you unprepared during the upcoming Annual Enrollment Period, which starts on Oct. 15 and runs through Dec. 7. New research shows that 33% of Medicare beneficiaries don’t realize they should receive their Annual Notice of Change letter by the end of September.   

If you or a loved one is enrolled in a Medicare Advantage or Part D plan, reviewing the Annual Notice of Change letter is a key first step in comparing your Medicare coverage options for 2027. Here are the three things to look for in your letter this year:

1. Changes to your Medicare plan benefits. Review your Annual Notice of Change letter for any changes to the covered benefits under your Medicare Advantage or Part D plan. Some plans may be leaving the market, while others could modify supplemental benefits such as dental, vision, hearing, transportation, fitness programs, or over-the-counter allowances. If your current plan is reducing or dropping benefits that are important to you, it’s a good idea to compare other available Medicare coverage options.

Take a close look at your prescription drug coverage as well. Medicare Advantage and Part D plans can update their lists of covered drugs from year to year, changing which medications are covered, moving drugs into different cost-sharing tiers, or adding new requirements such as prior authorization. If you regularly take prescription drugs, make sure your medications remain covered and that the costs still fit your budget.

2. Changes to your premiums and out-of-pocket costs. Compare what you'll pay in 2027 versus what you pay today. Medicare Advantage and Part D plans can change their monthly premiums, deductibles, copays, coinsurance, and prescription drug costs from one year to the next.

If you’re enrolled in a Medicare Advantage plan, it’s also important to review your annual out-of-pocket maximum and any changes to costs for primary care, specialist visits, outpatient services, hospital care, or medical equipment. Even modest cost increases can add up over the course of a year, particularly for people managing chronic health conditions or taking multiple medications.

3. Changes to your network of medical care providers and facilities. Medicare Advantage and Part D plans are offered by private insurance companies that contract with networks of doctors, hospitals, clinics, and pharmacies. These networks can change annually, making it important to confirm that your preferred providers will still be in-network for you in 2027.

If you’re enrolled in a Medicare Advantage plan, don’t stop with your primary care physician. Check whether your specialists, hospitals, facilities, urgent care centers, and local pharmacies remain in-network. If a care provider is no longer participating, you may face higher costs or need to switch care teams. Reviewing these changes before enrollment season can help you avoid surprises after your new coverage begins.

If you haven’t received your Annual Notice of Change letter by the end of September, contact your insurer or look for the document on your plan’s website or app. If you need help reviewing your coverage options for 2027, reach out to a licensed insurance agent who can help compare plans and identify coverage that best fits your personal health needs, prescriptions, and budget.

Whitney Stidom is vice president of consumer enablement at eHealth, an online health insurance marketplace that helps consumers navigate their health benefit decisions